BACKGROUND OF THE INVENTION
[0001] The present invention relates to an automatic lap splicing method. More specifically,
the present invention pertains to an automatic lap splicing method for a ribbon lap
machine or a comber that overlaps an end of a succeeding lap onto an end of a preceding
lap thereby splicing the laps.
[0002] A comber or a ribbon lap machine splices laps. That is, when the amount of the lap
being used (preceding lap) becomes small, the comber or the ribbon lap machine overlaps
an end of a succeeding lap (hereinafter, referred to as a succeeding lap end) onto
an end of the preceding lap (hereinafter, referred to as a preceding lap end), thereby
splicing the laps. Automatic lap splicing apparatuses, which automatically perform
such lap splicing, are disclosed, for example, in Japanese Laid-Open Patent Publications
No.
4-222234 and No.
4-257324. These automatic lap splicing apparatuses have a preceding lap end forming device,
which forms a preceding lap end, a succeeding lap end forming device, which forms
a succeeding lap end, and an overlap length setting device, which sets the length
of the succeeding lap end overlapped onto the preceding lap end. The overlap length
setting device adjusts the amount of forward rotation of a succeeding lap roll (a
lap feeding amount) after a succeeding lap end is formed, thereby setting the overlap
length of the succeeding lap end onto the preceding lap end.
[0003] The lap feeding amount is input by the operator prior to the lap splicing. Since
the fiber lengths of laps vary depending on the materials, an optimal length is not
always input as the overlap length of the preceding lap and the succeeding lap. Even
if the same material is used, the fiber distributions and the lengths of the lap ends
vary at the cut ends of the preceding lap and the succeeding lap. Therefore, the sizes
of slivers at the spliced parts vary in the comber.
SUMMARY OF THE INVENTION
[0005] Accordingly, it is an object of the present invention to provide an automatic lap
splicing method to obtain properly joining an end of a succeeding lap to an end of
a preceding lap.
[0006] This object is solved by a method having the features of claim 1.
[0007] Further developments are subject-matter of the dependent claims.
[0008] Other aspects and advantages of the present invention will become apparent from the
following description, taken in conjunction with the accompanying drawings, illustrating
by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The invention, together with objects and advantages thereof, may best be understood
by reference to the following description of the presently preferred embodiments together
with the accompanying drawings in which:
Fig. 1 is a partial plan view of a comber for performing an embodiment of the method
of the invention;
Fig. 2 is a side view showing a combing head in Fig. 1;
Fig. 3 is a partial side view, with a part cut away, illustrating the structure about
the nozzle pipe in Fig. 2;
Fig. 4 is a partial side view, with a part cut away, illustrating the structure about
the suction nozzle in Fig. 2;
Figs. 5A and 5B are side views schematically showing a cutting step for cutting an
end of a succeeding lap;
Figs. 6A and 6B are side views schematically showing the cutting step;
Figs. 7A and 7B are side views schematically showing a step for guiding the succeeding
lap end;
Figs. 8A and 8B are side views schematically showing a step for overlapping the succeeding
lap end and the preceding lap end; and
Figs. 9A to 9C are diagrams each showing an overlapped state of the succeeding lap
end and the preceding lap end.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] A comber 10 having an automatic lap splicing apparatus suitable for performing one
embodiment of the invention will now be described with reference to Figs. 1 to 9C.
[0011] As shown in Figs. 1 and 2, the comber 10 includes combing heads 11, which are arranged
parallel with each other. Each combing head 11 includes a pair of lap rollers 12,
on which lap rolls LW are placed. Hereinafter, the direction in which a lap L is delivered
from each lap roll LW is referred to as a forward direction (leftward direction as
viewed in Fig. 2, and a direction opposite to the delivering direction of the lap
L is referred to as a rearward direction (rightward direction as viewed in Fig. 2).
Each combing head 11 includes a combing section 13, a guiding plate 14, and a roller
section 15. The combing section 13 is located downstream of the lap rollers 12. The
guiding plate 14 guides fleece F, which is delivered after being subjected to the
combing effect of the combing section 13, and concentrates the fleece F. The roller
section 15 draws a sliver S, which is obtained by the concentration at the guiding
plate 14, and compresses the sliver S. A guide table 16 is provided on the downstream
side of the roller sections 15. The guide table 16 extends in a direction perpendicular
to the direction in which the slivers S are drawn, or in the lateral direction as
viewed in Fig. 1. The slivers S drawn from the combing heads 11 are engaged with guide
rollers 17 on the guide table 16 to change the moving direction and move to a draft
section 18 arranged to face one end of the guide table 16. The slivers S are bundled
(doubled) and drafted at the draft section 18. The slivers S are then stored in a
can by a coiling device (not shown).
[0012] As shown in Fig. 2, each combing head 11 includes, at a position forward of and below
the lap rollers 12, a nipper device 20, a combing cylinder 21, two pairs of detaching
rollers 22, and a top comb 23. The nipper device 20 has a feed roller 19. The roller
section 15 is located frontward of the detaching rollers 22, and the guiding plate
14 is located between the detaching rollers 22 and the roller section 15. The roller
section 15 includes a pair of delivery rollers (drawing rollers) 24 and calender roller
set 25, which includes a driver roller 25a and a driven roller 25b. The driver roller
25a is driven by a driveshaft that is common to all the combing heads 11. The driven
roller 25b is urged toward and driven by the driver roller 25a.
[0013] The nipper device 20 includes a nipper frame 26, which is pivotally supported on
the combing cylinder 21. The nipper frame 26 has a bottom nipper 27 at the bottom
in the front portion. The nipper frame 26 further has a top nipper 28. The top nipper
28 is opened and closed in synchronization with the pivoting motion of the nipper
frame 26 to nip the lap L with the bottom nipper 27.
[0014] A carrier roller 30 and a top roller 31 are arranged frontward of the lap rollers
12 and above the nipper device 20. The top roller 31 is movable between an operational
position, at which the top roller 31 is pressed against the carrier roller 30 from
above, and a retracted position, at which the top roller 31 is moved upward from the
operational position. The carrier roller 30 and the top roller 31 configure a preceding
lap end forming device (or means), which forms an end of a lap L being used, or a
preceding lap end, in lap splicing. Other than the time when forming a preceding lap
end, the top roller 31 is held at the retracted position, so that the lap L can be
moved freely on the carrier roller 30. A gas discharge pipe 32 is provided above and
in the vicinity of the top roller 31. The gas discharge pipe 32 is arranged parallel
with the top roller 31 and discharges gas (for example, air) downward from discharge
ports (not shown).
[0015] A nozzle pipe 33 is located between the carrier roller 30 and the front lap roller
12. The nozzle pipe 33 extends along the axis of the lap roll LW, which is placed
on the lap rollers 12, and over the entire axial length of the lap roll LW. The nozzle
pipe 33 is connected to a compressed air supply source (not shown) via a hose 34.
A suction nozzle 35 is located below the lap roll LW such that the distal end of the
suction nozzle 35 is located between the lap rollers 12. The suction nozzle 35 has
an opening that extends over the entire axial length of the lap roll LW and is connected
to a negative pressure source (not shown) via a hose 36.
[0016] As shown in Fig. 3, the nozzle pipe 33 has arms 37 attached to the axial ends and
is attached to the front lap roller 12 via these arms 37, which allows the nozzle
pipe 33 to pivot about the axis of the front lap roller 12. The nozzle pipe 33 has
a slit 33a, which extends parallel with an imaginary plane that includes the center
of pivoting motion of the arms 37 (the axis of the front lap roller 12) and the axis
of the nozzle pipe 33. The slit 33a is located at a position where the slit 33a is
allowed to deliver compressed air supplied by the compressed air supply source in
a direction from the proximal ends of the arms 37 toward the distal ends. The nozzle
pipe 33 has a guide plate 38, which guides the compressed air delivered by the slit
33a. The guide plate 38 extends parallel with the slit 33a and with the imaginary
plane. The nozzle pipe 33 can be arranged at a lap end drawing position, which is
represented by long dashed double-short dashed lines in Fig. 3, and an overlap guiding
position, which is represented by solid lines. When the nozzle pipe 33 is at the lap
end drawing position, the guide plate 38 is substantially parallel with the common
tangent of the lap roller 12 and the lap roll LW. When the nozzle pipe 33 is arranged
at the overlap guiding position, the distal end of the guide plate 38 is directed
to a point above the contact point between the carrier roller 30 and the top roller
31.
[0017] As shown in Fig. 4, the suction nozzle 35 has at its distal end a curved portion
35a, which is curved outward toward the rear lap roller 12, and a holding member 39,
which is located on the side opposite from the curved portion 35a. The holding member
39 can be tilted to a holding position, which is represented by long dashed double-short
dashed lines in Fig. 4. Specifically, the proximal end of the holding member 39 is
formed to be flexible, and a projection 40 is formed on the outer surface in the vicinity
of the holding member 39. The suction nozzle 35 includes a bracket 42 on the outer
surface close to the proximal end and a cylinder 41, which is rotationally attached
to the bracket 42. The cylinder 41 has a piston rod 41 a, which is rotationally coupled
to the projection 40. The holding member 39 is at the holding position when the piston
rod 41 a is protruded.
[0018] The pivots 12a of the lap rollers 12 are driven by a motor M for lap rollers that
is activated independently from the combing driving section. The lap roller driving
motor M is configured to be rotated in forward and reverse directions and is activated
via an inverter device 44, which is controlled based on commands from a controller
C. The controller C is, for example, a processor. During operation of the comber 10,
the controller C controls the lap roller driving motor M to rotate in the forward
direction, while conforming to predetermined driving conditions.
[0019] In lap splicing, the controller C controls the lap rollers 12 to be rotated in the
reverse direction with the lap L held by the carrier roller 30 and the top roller
31, so that the lap L is cut to form a preceding lap end. That is, the carrier roller
30, the top roller 31, the lap rollers 12, the lap roller driving motor M, and the
controller C configure a preceding lap end forming device (means).
[0020] With suction being created at the suction nozzle 35, the controller C drives the
lap rollers 12 to rotate in the forward direction and causes the suction nozzle 35
to suction an end of the lap L of a new lap roll LW. Then, with the suctioned lap
end being held by holding member 39, the controller C drives the lap rollers 12 to
rotate in the reverse direction to cut the lap L, thereby forming a succeeding lap
end. That is, the suction nozzle 35, the holding member 39, the lap rollers 12, the
lap roller driving motor M, and the controller C configure a succeeding lap end forming
device (means).
[0021] The controller C is connected to detecting sections 46, each of which corresponds
to one of the combing heads 11. When lap splicing is performed at the corresponding
combing head 11, each detecting section 46 detects an overlap thickness corresponding
amount, which corresponds to the thickness of a lap overlapping portion, at which
the succeeding lap end and the preceding lap end are overlapped. For each combing
head 11, the controller C changes a parameter related to the lap splicing in accordance
with the overlap thickness corresponding amount detected by the corresponding detecting
section 46. That is, the controller C functions as a parameter changing section, which
changes a parameter for each combing head 11 related to lap splicing in accordance
with the overlap thickness corresponding amount detected by the corresponding detecting
section 46.
[0022] In the present embodiment, the detecting sections 46 detect the sizes of the slivers
S before being doubled as the overlap thickness corresponding amounts. Specifically,
the driven roller 25b of each calender roller set 25 can be displaced with respect
to the driver roller 25a, so that the interaxial distance of the rollers 25a, 25b
is adjusted. Also, the driven roller 25b is urged toward the driver roller 25a by
a spring. The driven roller 25b is thus displaced such that the interaxial distance
of the rollers 25a, 25b is changed in accordance with the size of the sliver S. As
the detecting section 46, a distance sensor that continuously detects the distance
between the driven roller 25b and the driver roller 25a is used. According to the
invention, the parameter related to lap splicing is the length of the overlapping
portion of a succeeding lap end and a preceding lap end (overlap length). The controller
C receives detection signals from the detecting sections 46. For each combing head
11, the controller C calculates the size of the sliver S in a part that corresponds
to the spliced lap portion based on the detection signal, the operation time of the
comber from when the lap splicing ended, and the operating condition. When the size
of the sliver S at the portion is out of a predetermined range, the controller C changes
the overlap length. The overlap length is determined by the amount of forward rotation
of the lap rollers 12 after a succeeding lap end is formed and the lap rollers 12
are stopped.
[0023] The controller C changes the overlap length in the following manner. That is, the
controller C shortens the overlap length when the size of the sliver S is above the
predetermined range and lengthens the overlap length when the size of the sliver S
is below the predetermined range. The extent of changes in the overlap length is stored
in a memory of the controller C in advance through experimentation.
[0024] Operation of the automatic lap splicing apparatus of the above described configuration
will now be described, using one of the combing heads 11 as an example. The other
combing heads 11 operates in a manner similar to the following description.
[0025] Lap splicing is performed when the amount of the lap roll LW is decreased to a predetermined
amount by operation of the comber 10. The lap splicing is performed after the operation
of the comber 10 is stopped. First, the top roller 31 is moved from the retracted
position to the operational position so that the top roller 31 and the carrier roller
30 cooperate to hold the lap L, which has been guided to the nipper device 20 from
the lap roll LW via the carrier roller 30. In this state, the lap roller driving motor
M is driven to rotate in the reverse direction so that the lap roll LW reels in the
lap L. The lap L is then cut between the front lap roller 12 and the position where
the carrier roller 30 and the top roller 31 hold the lap L, so that a preceding lap
end is formed. After the lap L is cut, the lap roll LW is removed from the lap rollers
12, and a new lap roll LW is placed on the lap rollers 12.
[0026] Then, as shown in Fig. 5A, the nozzle 35 is maintained in a suction state, in which
negative pressure is supplied, and the lap rollers 12 are driven to rotate in the
forward direction. The suction nozzle 35 suctions an end of the lap L of the new lap
roll LW. In this state, the preceding lap end E1 is located rearward of the carrier
roller 30 and the top roller 31. Subsequently, as shown in Fig. 5B, the end of the
lap L of the new lap roll LW is suctioned by the suction nozzle 35 to a position where
the holding member 39 of the suction nozzle 35 can hold the lap end. The lap rollers
12 are then stopped and the holding member 39 is arranged at the holding position,
so that the end of the lap L is held by the holding member 39 and the curved portion
35a.
[0027] Next, as shown in Fig. 6A, the lap rollers 12 are driven to rotate in the reverse
direction, and the lap L is cut between the rear lap roller 12 and the position where
the lap L is held by the holding member 39 and the curved portion 35a, so that a succeeding
lap end E2 is formed. Then, the lap rollers 12 are stopped as shown in Fig. 6B. Also,
supply of negative pressure to the suction nozzle 35 is stopped, and the holding member
39 is arranged at the retracted position.
[0028] Next, as shown in Fig. 7A, the nozzle pipe 33 is arranged at the lap end drawing
position, and the guide plate 38 is arranged to be substantially parallel with the
common tangent of the front lap roller 12 and the lap roll LW. Thereafter, when the
lap rollers 12 are driven to rotate in the forward direction, compressed air is discharged
from the slit 33a of the nozzle pipe 33. The succeeding lap end E2 is moved toward
the front lap roller 12 by the forward rotation of the lap rollers 12, and then contacts
and moves over the front lap roller 12. When contacting and moving over the front
lap roller 12, the succeeding lap end E2 is pressed against the lap roll LW.
[0029] The compressed air discharged from the slit 33a moves along the guide plate 38, which
extends from a position close to the front lap roller 12 and parallel with the common
tangent of the lap roller 12 and the lap roll LW. Thus, the compressed air discharged
from the slit 33a creates a negative pressure in a zone on the surface of the lap
roll LW that is close to the proximal end of the guide plate 38. The negative pressure
separates the succeeding lap end E2, which is pressed against the lap roll LW, from
the surface of the lap roll LW. This allows the succeeding lap end E2 to move along
the surface of the guide plate 38 as the lap roll LW is rotated in the forward direction
as shown in Fig. 7B. When a predetermined time has elapsed, the rotation of the lap
rollers 12 is stopped. At this time, the tip of the succeeding lap end E2 is located
forward of the distal end of the guide plate 38.
[0030] Next, the nozzle pipe 33 is moved from the lap end drawing position to the overlap
guiding position as shown in Fig. 8A. The distance from the contact position between
the front lap roller 12 and the lap roll LW to the distal end of the guide plate 38
changes between when the nozzle pipe 33 is arranged at the lap end drawing position
and when the nozzle pipe 33 is located at the overlap guiding position. Specifically,
the distance is longer when the nozzle pipe 33 is arranged at the overlap guiding
position. Thus, as the nozzle pipe 33 is moved from the lap end drawing position to
the overlap guiding position with the lap rollers 12 in a stopped state, the tip of
the succeeding lap end E2 is moved toward the proximal end of the guide plate 38.
As a result, when the nozzle pipe 33 is arranged at the overlap guiding position,
the length of the part of the succeeding lap end E2 that extends from the distal end
of the guide plate 38 is short in comparison with a case in which the nozzle pipe
33 is arranged at the lap end drawing position.
[0031] In this regard, the lap rollers 12 are driven to rotate in the forward direction
as the nozzle pipe 33 is moved from the lap end drawing position to the overlap guiding
position such that the length of the part of the succeeding lap end E2 that extends
from the distal end of the guide plate 38 is equalized between when the nozzle pipe
33 is arranged at the lap end drawing position and when the nozzle pipe 33 is located
at the overlap guiding position. The amount of the forward rotation of the lap rollers
12 is determined such that, when the nozzle pipe 33 arranged at the overlap guiding
position, the length of the part of the succeeding lap end E2 that extends from the
distal end of the guide plate 38 corresponds to an desired overlap length of the preceding
lap end E1 and the succeeding lap end E2. The discharge of the compressed air from
the slit 33a is stopped when the nozzle pipe 33 is being moved from the lap end drawing
position to the overlap guiding position, so that the compressed air discharged from
the slit 33a does not adversely affect the preceding lap end E1 in a state in which
the guide plate 38 is arranged to face the preceding lap end E1 as the nozzle pipe
33 is moved. As a result, as illustrated in Fig. 8A, when the nozzle pipe 33 is arranged
at the overlap guiding position, the succeeding lap end E2, which protrudes from the
distal end of the guide plate 38, is overlapped onto the preceding lap end E1.
[0032] Then, as shown in Fig. 8B, the lap rollers 12 are driven to rotate in the forward
direction, and the carrier roller 30 is rotated in a direction for feeding the preceding
lap end E1. The gas discharge pipe 32 discharges compressed air to the overlapping
portion of the preceding lap end E1 and the succeeding lap end E2. The compressed
air discharged from the gas discharge pipe 32 intertwines the fibers in the overlapping
portion of the preceding lap end E1 and the succeeding lap end E2. Thereafter, the
overlapping portion passes between the carrier roller 30 and the top roller 31 while
being pressed by the rollers 30, 31. The lap splicing is thus completed. In Figs.
5A to 8B, components such as the arms 37 and the cylinder 41 are omitted.
[0033] After completion of the lap splicing, the comber 10 is started. The spliced lap portion
passes through the combing section 13 to form a sliver S. When the sliver S is delivered
to the guide table 16 via the calender roller set 25, the detecting section 46 detects
the size of the sliver S, which is an overlap thickness corresponding amount, which
corresponds to the thickness of the lap overlapping portion. The controller C receives
a detection signal from the detecting section 46 and determines whether the detected
size of the sliver S is within a range that corresponds to a predetermined proper
thickness of the spliced lap portion. If the size of the sliver S is displaced from
the predetermined range, the controller C changes a parameter related to the lap splicing
to reduce the amount of displacement and performs the next lap splicing operation
based on the changed parameter.
[0034] After the lap splicing is performed, if the size of the sliver S detected by the
detecting section 46 is displaced from the predetermined range, the controller C changes
a parameter related to the next lap splicing, that is, the overlap length, such that
the amount of displacement will be reduced. If the size of the sliver S detected by
the detecting section 46 is within the predetermined range, the next lap splicing
operation will be performed under the same conditions. Therefore, if the thickness
of the lap overlapping portion is displaced from the predetermined range, the lap
splicing is repeated while changing the value of a parameter, so that the lap ends
E1, E2 are joined in a proper manner.
[0035] In the lap splicing, the lap L is not cut with a cutting tool. Instead, with a part
held, the lap L is cut by being pulled at a position separated from the held part.
That is, the lap L is cut when the fibers forming the lap L are pulled and separated
between the held side and the pulled side. Therefore, the fiber density of the cut
ends of the lap L is smaller than that in the other parts as schematically illustrated
in Figs. 9A to 9C. If the cut section of the preceding lap end E1 and the cut section
of the succeeding lap end E2 are properly overlapped at the overlapping portion of
the preceding lap end E1 and the succeeding lap end E2 as shown in Fig. 9A, the fibers
in the lap L are uniformized at the joint, so that the fibers in the sliver S made
of the lap L is uniformized.
[0036] However, if the overlap length of the cut section of the preceding lap end E1 and
the cut section of the succeeding lap end E2 is shorter than the proper overlap length
by a length Ls as illustrated in Fig. 9B, the lap L will be thin at the joint, and
the size of the sliver S made of the lap L will be small at the part corresponding
to the joint. Also, if the overlap length of the cut section of the preceding lap
end E1 and the cut section of the succeeding lap end E2 is longer than the proper
overlap length by a length Lf as illustrated in Fig. 9C, the lap L will be thick at
the joint, and the size of the sliver S made of the lap L will be great at the part
corresponding to the joint. In this regard, if the size of the sliver S, which is
detected by the detecting section 46, is out of the predetermined range, the controller
C changes a parameter related to the lap splicing such that the amount of displacement
decreases, and performs the next lap splicing operation. Therefore, even if the initially
set overlap length is not proper, the overlap length will be properly controlled in
repetitive executions of the lap splicing.
[0037] The present embodiment achieves the following advantages.
- (1) The comber 10 for performing the method of the invention includes the automatic
lap splicing apparatus, which overlaps and joins a succeeding lap end and a preceding
lap end. The automatic lap splicing apparatus includes the detecting sections 46 and
the parameter changing section (the controller C). The detecting sections 46 each
detect an overlap thickness corresponding amount, which corresponds to the overlap
thickness of a lap overlapping portion. For each combing head 11, the parameter changing
section changes a parameter related to the lap splicing in accordance with the overlap
thickness corresponding amount detected by the detecting section 46. Therefore, if
the thickness of the lap overlapping portion in each combing head 11 is out of the
predetermined range, the lap splicing is repeated while changing the value of the
parameter, so that the preceding lap end E1 and the succeeding lap end E2 are joined
in a proper manner.
- (2) The detecting sections 46 detect the sizes of the slivers S before doubling. In
the case of the comber 10, the thickness of the lap overlapping portion is not detected
in each combing head 11. Instead, the size of the sliver S, which has been combed
by the combing head 11 to become the fleece F and concentrated by the guiding plate
14, is detected as the lap overlap thickness corresponding amount. Compared to a case
in which the thickness of a lap overlapping portion is detected, variation of the
detection accuracy is small. In the comber 10, other than the slivers S formed by
the combing heads 11, there is a sliver S that is formed by doubling and drafting
the slivers S formed by the combing heads 11. The detecting accuracy is higher when
the sizes of the slivers S before doubling are detected than when the size of the
doubled sliver S is detected.
- (3) The parameter related to the lap splicing is the overlap length of the preceding
lap end E1 and the succeeding lap end E2. Parameters that affect the thickness of
the lap overlapping portion include the overlap length and the extent of intertwining
of the fibers at the lap overlapping portion. The overlap length affects the lap overlap
thickness by a greater extent than the extent of the intertwining. Thus, using the
overlap length as the parameter related to the lap splicing ensures high detection
accuracy.
[0038] The present embodiment is not limited to the above configuration, but may be modified
as follows.
[0039] In the above illustrated embodiment, the size of the sliver S is detected at the
calender roller set 25 as the overlap thickness corresponding amount, which correspond
to the thickness of the lap overlapping portion. Instead, the thickness of a lap passing
through between the carrier roller 30 and the top roller 31 may be detected. For example,
the top roller 31 may be configured to be movable at the operational position in accordance
with the thickness of the lap L, and the movement amount may be detected.
[0040] The detecting section 46, which detects the size of the sliver S, is not limited
to a distance sensor that detects the distance between the driver roller 25a and the
driven roller 25b, which form the calender roller set 25. For example, a trumpet may
be arranged between the guiding plate 14 and the delivery roller 24, and the trumpet
may be provided with a detecting section that detects the size of the sliver passing
through the trumpet. The detecting section may include a detecting member that is
contactable with the sliver passing through the trumpet and may be configured to detect
changes in the position of the detecting member. The detecting member is urged by
an urging member such as a spring so that the position of the detecting member is
changed in accordance with the size of the sliver passing through the trumpet.
[0041] The detecting section 46, which detects the size of the sliver S, is not limited
to a mechanical sensor. That is, the detecting section 46 does not necessarily need
to be moved in accordance with the size of the sliver S to detect the amount of the
movement. Instead, the detecting section 46 may be a capacitance sensor.
[0042] Instead of the size of the sliver S prior to doubling, the size of the sliver S after
doubling and drafting at the draft section 18 may be detected. However, in the doubled
sliver, it is difficult to localize a part that corresponds to the spliced lap portion
of the slivers before doubling. Thus, the detection accuracy is higher if the size
of the sliver S before doubling is detected.
[0043] The slit 33a of the nozzle pipe 33 may be replaced by a number of holes, so that
compressed air is discharged though the holes.
[0044] The parameters related to the lap splicing may include, in addition to the overlap
length, the flow rate or the time duration of discharge of air onto the overlapping
portion of the succeeding lap end E2 and the preceding lap end E1. The intertwined
state of the fibers of the succeeding lap end E2 and the fibers of the preceding lap
end E1 varies depending on the flow rate or time duration of discharge of air onto
the overlapping portion, and the size of the sliver is changed in accordance with
the intertwined state of the fibers. If the amount of intertwined fibers of the succeeding
lap end E2 and the preceding lap end E1 is small, the sliver is formed to have a relatively
small size because the sliver is pulled in the middle of lap splicing. The air discharge
flow rate or discharge time duration is thus decreased when the size of the sliver
S is above the predetermined range, and is increased when the size of the sliver S
is below the predetermined range. The extent of changes in the overlap length and
the extent of changes in the air discharge flow rate or the air discharge time duration
are stored in a memory of the controller C in advance through experimentation. If
the parameters include, in addition to the overlap length, the flow rate or the time
duration of discharge of air discharged onto the overlapping portion, the preceding
lap end E1 and the succeeding lap end E2 can be more properly joined compared to a
case in which only the overlap length is used as a parameter.
[0045] In the illustrated embodiment, the parameter is changed each time the detecting section
46 detects the overlap thickness corresponding amount after lap splicing is executed
in each combing head 11. The present invention is not limited to this. Specifically,
the parameter may be changed based on the average value of the overlap thickness corresponding
amounts that have been detected over several operations in the past by the detecting
section 46 or based on another functional calculus such as the least squares method.
[0046] The center of pivoting motion of the arms 37 does not necessarily need to be located
at the same position as the axis of the front lap roller 12. For example, the center
of pivoting motion of the arms 37 may be arranged such that the distance from the
contact position between the front lap roller 12 and the lap roll LW to the distal
end of the guide plate 38 remains the same between when the nozzle pipe 33 is arranged
at the lap end drawing position and when the nozzle pipe 33 is located at the overlap
guiding position. In this case, the lap rollers 12 do not need to be driven when the
nozzle pipe 33 is moved to the overlap guiding position after the nozzle pipe 33 is
arranged at the lap end drawing position, the succeeding lap end E2 is drawn from
a new lap roll LW, and rotation of the lap rollers 12 is stopped.
[0047] The nozzle pipe 33 does not necessary need to be moved between the lap end drawing
position and the overlap guiding position by the pivotal arms 37. For example, the
nozzle pipe 33 may be moved between the lap end drawing position and the overlap guiding
position by a robotic arm.
[0048] The guide plate 38 of the nozzle pipe 33 does not necessarily need to be formed to
extend radially outward from the center of the nozzle pipe 33. For example, the guide
plate 38 may be formed to extend substantially along a tangent of the nozzle pipe
33, and the slit 33a may be formed to discharge air substantially along the tangent.
[0049] The present invention is not limited to an automatic lap splicing apparatus of a
comber, but may be applied to an automatic lap splicing apparatus of a ribbon lap
machine.
[0050] Adjustment of the parameter in the automatic lap splicing apparatus does not necessarily
need to be performed at replacement of lap rolls LW, but may be performed during initial
setting of a comber or a ribbon lap machine by repeating lap splicing several times
with a new lap roll LW to adjust the parameter to a proper value. In the comber 10,
the lap roll LW is replaced after approximately two hour continuous operation. At
replacement of the lap roll LW, it takes a long time to obtain the optimal conditions
if the parameter is adjusted based on the detection results of the detecting sections
46. However, if the operation is started after repeating lap splicing to adjust the
parameter to obtain the optimal operational state at the initial setting, the comber
or the ribbon lap machine is permitted to operate to obtain the optimal spliced lap
portion.
[0051] Therefore, the present examples and embodiments are to be considered as illustrative
and not restrictive and the invention is not to be limited to the details given herein,
but may be modified within the scope of the appended claims.
An automatic lap splicing apparatus for a ribbon lap machine or a comber is provided.
The apparatus performs lap splicing by overlapping and joining an end of a succeeding
lap and an end of a preceding lap. The apparatus being includes a detecting section
and a parameter changing section. The detecting section detects an overlap thickness
corresponding amount, which corresponds to a thickness of an overlapping portion of
the succeeding lap and the preceding lap. The parameter changing section changes a
parameter related to lap splicing in accordance with the overlap thickness corresponding
amount detected by the detecting section.